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fall  2004
issue 10.2

It's in your hands

With this year's flu-vaccine shortage has come a barrage of flu-prevention tips, chief among them the admonition to wash your hands often.

Though it sounds like the advice you got from your mother in childhood, MIT internist and infectious disease specialist Howard Heller, M.D., says that "hand hygiene"—which includes frequent hand-washing—is one of the best ways to avoid not only the flu, but also colds. "Most respiratory viral infections, including influenza, are spread through indirect contamination," he explains. "Viruses can live on the surfaces of objects for several hours. So, when you touch a surface that has been contaminated by an infected person, and then touch your nose or mouth, you can spread the virus to your own body." But, says Heller, by keeping your hands clean—using soap and water or an alcohol-gel hand sanitizer—you can stop indirect contamination at the source.

When should I wash my hands?

Most of us have heard about the studies concluding that Americans don't wash their hands often enough. But when should we wash?

First of all, Heller says, you should wash your hands any time they are visibly dirty. But, he adds, even when your hands appear clean, they may be contaminated and capable of spreading illness to yourself or others. Therefore, say infectious disease experts, you should also wash or sanitize your hands:

  • Before and after food preparation, handling, and serving,
  • Before you eat,
  • Before and after caring for someone who is sick, very young, or very old,
  • After using the bathroom,
  • After changing a diaper,
  • After blowing your nose with a tissue or covering a cough or sneeze with your hands,
  • After coming into contact with any bodily fluid such as saliva, urine, blood, or mucous,
  • After handling animals, and
  • After touching objects or surfaces that may have been touched by a number of other people before you, including shared workplace equipment such as copiers, computers, telephones, and fax machines.

This last bit of advice is especially important for avoiding cold and flu germs from other people, says Heller. "Though it may make you appear a bit obsessive, washing your hands or using an alcohol-gel hand cleaner after touching surfaces that may have been previously touched by large numbers of people, such as door handles and gym equipment, can significantly reduce your risk of picking up respiratory viruses that have been deposited there by other users," he emphasizes.

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You've read the article, now watch the movie!

Click on one of the links below to watch a short video demonstrating proper hand-washing technique.

How should I wash my hands?

Good hand-washing technique includes using warm water and enough soap, rubbing the hands together to create friction, rinsing under running water, and being careful not to immediately contaminate your hands again on the water tap or bathroom door handle. Follow these steps:

  1. Wet your hands thoroughly with warm running water.
  2. Use soap, and rub your hands together to work up lather. Do this away from running water, so the lather is not washed away.
  3. Scrub the front and back of your hands, between your fingers, around your wrists and forearms, and under your nails for 15 to 20 seconds—approximately the length of time it takes to sing two verses of "Row, Row, Row Your Boat" or the "happy birthday song." (Of course, when using a public restroom, it's best to sing quietly or silently.)
  4. Rinse hands thoroughly under warm running water.
  5. Pat your hands dry with a single-use paper towel.
  6. Use the same paper towel to turn off the water taps to avoid a recontamination of your clean hands. You can also use this towel to open the bathroom door as you leave.

Alternatives to soap and water

Heller describes himself as a big fan of hand sanitizers that are available as a liquid or on wipes or towelettes. To be effective against viruses, a hand sanitizer should contain at least 60 percent ethyl alcohol. Since alcohol has a drying effect on the skin, many products also include moisturizers or skin-softening agents.

To use a liquid hand sanitizer, apply a thumb-size amount of gel in the palm of one hand, and rub your hands together briskly for at least 15 seconds, making sure to distribute the gel to fingertips, between fingers, and around the back of each hand. "It's not always practical or possible to wash one's hands with soap and water every time we should do so," Heller says. "But it's easy enough to carry around a small container of hand sanitizer, so you'll be able to clean your hands when necessary."

It's important to note, Heller adds, that alcohol-gel hand sanitizers work only on hands that are not visibly soiled.

More "hand-y" tips

In addition to keeping your hands clean, you should also try to keep your hands away from your face, Heller says. This may mean developing new habits. For example, when Heller finds himself at a party where he needs to shake a lot of hands, he tries to handle food only with his left hand. "I'm not actually ambidextrous, so I may appear a bit awkward," Heller laughs, "but it keeps that right hand—which is full of other people's germs—away from my nose and mouth."

Heller also reminds individuals to cover their own coughs and sneezes with a tissue. "And if you don't have a tissue handy," he says, "cough or sneeze into your upper sleeve, not your hands."

Additional resources


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